Pancreatic adenocarcinoma is the fourth leading cause of adult cancer mortality in the United States. At the time of diagnosis, most pancreatic cancer patients present with advanced disease. The failure to develop effective treatment for advanced pancreatic cancer is due to the lack of a better understanding of the interplay of its numerous genetic alterations and specific signaling pathways that mediate the aggressive tumor biology of pancreatic cancer. Recently, a key point that has emerged from analysis of the molecular biology of pancreatic cancer is that this disease exhibits a unique profile of genetic and molecular alterations that distinguish this malignancy from all other others, suggesting that these molecular alterations are the possible targets against which innovative therapeutic approaches should be designed. We have been seeking to identify the specific signaling networks that are thought to play key roles in the acquisition of tumorgenicity by normal pancreatic ductal epithelial cells, and the invasive, angiogenic and metastatic phenotypes by human pancreatic adenocarcinoma. Our results show that overexpression of EGFR plays an important role in pancreatic cancer and we identified a negative regulator of EGFR which can inhibit EGFR and NF-kappaB. Furthermore, we demonstrated that inhibition of constitutive NF-kappaB activity by a dominant negative I kappa B alpha suppressed liver metastasis of pancreas cancer cells in an orthotopic nude mouse model, suggesting that constitutive RelA activity plays a key role in pancreas cancer metastasis. This experimental evidence suggests that EGFR inhibitors (IMC-C225 and ERRP), genistein, and the NF-kappa B inhibitor (PS-341) are potentially effective therapeutic agents for pancreatic cancer. In this Project, we will test our hypothesis that inhibition of NF-kappaB and EGFR signaling pathways by these agents alone or in combination with gemcitabine will potentiate cytotoxic agent-induced apoptosis in human pancreatic cancer cells and lead to greater therapeutic effects. Using preclincal systems, our findings will provide a better understanding of the role of cellular signal transduction inhibitors and their ability to sensitize cells to apoptosis. Insights gained into the mechanism of action of these signaling inhibitors will be used to design current and future clinical trials.